In a wireless communication system, a wireless device communicates with an access node using a wireless communication link. The physical layer of the wireless communications link, such as a frequency or frequencies, can comprise one or more logical channels. Communications from the access node to the wireless device are typically referred to as downlink communications, and communications from the wireless device to the access node are typically referred to as uplink communications.
Each of the uplink and downlink communications can comprise one or more portions for bearer data, for example, related to voice or data communications, and one or more portions for non-bearer data. The physical random access channel (PRACH) is a physical channel in the uplink which is used for non-bearer data, such as network entry and wireless link resource requests. Physical resources, such as sub-frames, which are allocated to the PRACH typically cannot be used to carry other information, such including bearer data.
Overview
In operation, loading information of an access node and a random access failure rate at the access node are determined, where the access node is using a first physical random access channel (PRACH) index. The loading information is compared to a loading criteria, and the random access failure rate is compared to a failure rate criteria. Based on the comparison of the loading information to the loading criteria and the comparison of the random access failure rate to the failure rate criteria, a second PRACH configuration index is selected for the access node.